A new preservation system that pumps cooled, oxygen-rich fluid into donor livers not only keeps the organs in excellent condition for as long as nine hours before transplantation, but also leads to dramatically better liver function and increases survival of recipients, according to a series of animal studies by researchers at the University of Pittsburgh School of Medicine and the McGowan Institute for Regenerative Medicine. The system could be tested with transplant patients at UPMC later this year.
The findings, which were published online in the American Journal of Transplantation, suggest that it’s possible to use the technique of “machine perfusion” with a newly created cell-free oxygenated solution to expand the number of high-quality livers available for transplant, thereby shortening waiting times and reducing patient mortality.
Currently, 20 to 40 percent of donor livers cannot be transplanted into recipients because oxygen deprivation during storage and transportation in conventional containers can make pre-existing tissue damage worse, explained senior investigator Paulo Fontes.
The research team optimized a machine-perfusion (MP) device that was developed by Organ Assist, a company in the Netherlands, and added a fluid with a hemoglobin-oxygen carrier component to deliver high concentrations of oxygen to the tissue. The liver is immersed in chilled fluid, which is also pumped through tubes inserted into the organ’s large blood vessels to effectively oxygenate the tissue.